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281.
Molecular Systematics and the Conservation of Rare Species 总被引:10,自引:0,他引:10
Abstract: Despite the tradition of systematic biology as the science of diversity, systematics has until recently contributed relatively little to the theory and practice of conservation biology. We identify four areas in which systematics could contribute to the conservation of rare plant species: (1) species concepts, (2) the identification of lineages worthy of conservation, (3) the setting of conservation priorities, and (4) the effects of hybridization on the biology and conservation of rare species. Species concepts that incorporate history and reflect phylogeny ultimately will be more useful for preserving biodiversity than those that do not. Phylogenetic analyses involving conspecific populations often reveal multiple lineages that may warrant protection as evolutionarily distinct units. Phylogenetic information also should be considered in setting priorities for conservation. Systematics provides the tools for inferring relationships among organisms and, in conjunction with biogeography, for identifying those areas that harbor many actively speciating groups. Hybridization may lead to the extinction of a rare species, but in other cases, ironically, artificial hybridization with a more widespread congener may be the only way to preserve the gene pool of a rare species. We appeal to systematists to contribute actively to both conservation theory and practice, and we call for the integration of systematics in the establishment of conservation priorities and the development of strategies to preserve Earth's biota. 相似文献
282.
Tim Caro Jeffrey Andrews Matthew Clark Monique Borgerhoff Mulder 《Conservation biology》2023,37(1):e14011
We considered a series of conservation-related research projects on the island of Pemba, Tanzania, to reflect on the broad significance of Beier et al.’s recommendations for linking conservation science with practical conservation outcomes. The implementation of just some of their suggestions can advance a successful coproduction of actionable science by small research teams. Key elements include, first, scientists and managers working together in the field to ensure feedback in real time; second, questions jointly identified by managers and researchers to facilitate engaged collaboration; third, conducting research at multiple sites, thereby broadening managers’ abilities to reach multiple stakeholders; and fourth, establishing a multidisciplinary team because most of the concerns of local managers require input from multiple disciplines. 相似文献
283.
Yard EE Gilchrist J Haileyesus T Murphy M Collins C McIlvain N Comstock RD 《Journal of Safety Research》2010,41(6):471-474
Introduction
Heat illness is a leading cause of death and disability among U.S. high school athletes.Methods
To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009.Results
During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported.Conclusions
Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities.Impact of industry
By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths. 相似文献284.
Lee S Xu Q Booth M Townsend TG Chadik P Bitton G 《Waste management (New York, N.Y.)》2006,26(5):526-533
The biological conversion of sulfate from disposed gypsum drywall to hydrogen sulfide (H(2)S) in the anaerobic environment of a landfill results in odor problems and possible health concerns at many disposal facilities. To examine the extent and magnitude of such emissions, landfill gas samples from wells, soil vapor samples from the interface of the waste and cover soil, and ambient air samples, were collected from 10 construction and demolition (C&D) debris landfills in Florida and analyzed for H(2)S and other reduced sulfur compounds (RSC). H(2)S was detected in the well gas and soil vapor at all 10 sites. The concentrations in the ambient air above the surface of the landfill were much lower than those observed in the soil vapor, and no direct correlation was observed between the two sampling locations. Methyl mercaptan and carbonyl sulfide were the most frequently observed other RSC, though they occurred at smaller concentrations than H(2)S. This research confirmed the presence of H(2)S at C&D debris landfills. High concentrations of H(2)S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at C&D debris landfills when involved in excavation, landfill gas collection, or confined spaces. The results indicate that H(2)S is sufficiently diluted in the atmosphere to not commonly pose acute health impacts for these landfill workers in normal working conditions. H(2)S concentrations were extremely variable with measurements occurring over a very large range (from less than 3 ppbv to 12,000 ppmv in the soil vapor and from less than 3 ppbv to 50 ppmv in ambient air). Possible reasons for the large intra- and inter-site variability observed include waste and soil heterogeneities, impact of weather conditions, and different site management practices. 相似文献
285.
Schewe Rebecca L. Hoffman David Witt Joseph Shoup Brian Freeman Matthew 《Environmental management》2020,65(1):74-87
Environmental Management - This study examines the engagement of Vietnamese American commercial fisheries stakeholders in the US Gulf Coast with state and federal agencies and the role that citizen... 相似文献
286.
Matthew R. Herman A. Pouyan Nejadhashemi Juan Sebastian Hernandez‐Suarez Ali M. Sadeghi 《Journal of the American Water Resources Association》2020,56(4):738-755
The goal of this paper was to statistically explore the spatiotemporal performance of remotely sensed actual evapotranspiration (ETa) datasets and a remotely sensed ensemble in a region that lacks observed data. The remotely sensed datasets were further compared with ETa results from a physically based hydrologic model (Soil and Water Assessment Tool) to examine the differences and determine the level of agreement between the ETa datasets and the model outputs. ETa datasets were compared on temporal (i.e., monthly and seasonal basis) and spatial (i.e., landuse) scales at both watershed and subbasin levels. The results showed a lack of consistent similarities and differences among the datasets when evaluating the monthly ETa variations; however, the seasonal aggregated data presented more consistent similarities and differences during the spring and summer compared to the fall and winter. Meanwhile, spatial analysis of the datasets showed the MOD16A2 500 m ETa product was the most versatile of the tested datasets, being able to differentiate between landuses during all seasons. Furthermore, the use of an averaging ensemble was able to improve overall ETa performance in the study area. This study showed that the remotely sensed ETa products are not similar throughout the year, but the appropriate application periods for different ETa products were identified. Finally, spatial variabilities of the ETa products are more in tune with landuse and climate characteristics. 相似文献
287.
Sunday A. Adebusoye Matthew O. Ilori Oluwafemi S. Obayori Ganiyu O. Oyetibo Kehinde A. Akindele Olukayode O. Amund 《The Environmentalist》2010,30(1):24-34
Soil artificially contaminated with diesel oil, treated with cassava steep liquor (CSL) and designated EXPS. Similar polluted
soil without CSL amendment (CSS1) and uncontaminated soil (CSS2) served as controls. There were dramatic changes in the physico-chemistry
of systems EXPS and CSS1 with utilization of the inorganic nutrients to near-depletion in the former than the latter. In contrast,
the properties of CSS2 remained relatively stable throughout the investigated period. Similarly, the population densities
of microflora in the polluted soils showed an initial decrease between days 0 and 5 before assuming an increasing trend with
percent hydrocarbon-utilizers ranging significantly (P < 0.05) from 0.56 to 6.6, 0.1 to 2.46 and 0.56 to 0.26, respectively for EXPS, CSS1, and CSS2. In EXPS, the residual oil
decreased from 98,045 to 1,102.3 mg/kg soil at day 35 representing about 98.88% degradation. The corresponding value for CSS1
was 98,106.1 to 52,110 mg/kg soil, amounting to 46.88% oil disappearance. The GC fingerprints of alkane fractions of the recovered
oil reduced significantly by day 15 for EXPS with near-similar results of CSS1. However, by day 35, there was complete disappearance
of all peaks including the pristane and phytane molecules in the former whereas in CSS1, there were no observable changes.
The germination and growth profiles of maize seed plants as evidence of recovery of oil-impacted soils were poor in CSS1 (10%)
with pronounced abnormal morphology when compared with the data obtained for EXPS (74%) and CSS2 (80%). These results suggest
that CSL could be an indispensable tool in bioremediation of environments contaminated with hydrocarbons. The technology of
application is simple, rapid and cost-effective and may be appropriate for use in developing countries to ameliorate the problems
of petroleum pollution. 相似文献
288.
Annika Åberg Mats Tysklind Tohr Nilsson Matthew MacLeod Annika Hanberg Rolf Andersson Sture Bergek Richard Lindberg Karin Wiberg 《Environmental science and pollution research international》2010,17(1):26-39
Background, aim, and scope
The main pathway for human exposure to the highly toxic polychlorinated-p-dioxins and polychlorinated furans [polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)] is via dietary intake. Other exposure pathways may, however, be important in close proximity to point sources, such as wood preservation sites, where PCDD/F contaminated chlorophenols (CP) were previously used. In this study, a heavily PCDD/F contaminated CP saw mill site in Sweden was investigated. Human exposure through a broad spectrum of exposure pathways was assessed. Such studies are in demand since the question whether contaminated sites represent a current or future risk can only be answered by detailed site-specific risk assessments. 相似文献289.
Gardner T Acosta-Martinez V Calderón FJ Zobeck TM Baddock M Van Pelt RS Senwo Z Dowd S Cox S 《Journal of environmental quality》2012,41(3):744-753
Little is known about the microbial communities carried in wind-eroded sediments from various soil types and land management systems. The novel technique of pyrosequencing promises to expand our understanding of the microbial diversity of soils and eroded sediments because it can sequence 10 to 100 times more DNA fragments than previous techniques, providing enhanced exploration into what microbes are being lost from soil due to wind erosion. Our study evaluated the bacterial diversity of two types of wind-eroded sediments collected from three different organic-rich soils in Michigan using a portable field wind tunnel. The wind-eroded sediments evaluated were a coarse sized fraction with 66% of particles >106 μm (coarse eroded sediment) and a finer eroded sediment with 72% of particles <106 μm. Our findings suggested that (i) bacteria carried in the coarser sediment and fine dust were effective fingerprints of the source soil, although their distribution may vary depending on the soil characteristics because certain bacteria may be more protected in soil surfaces than others; (ii) coarser wind-eroded sediment showed higher bacterial diversity than fine dust in two of the three soils evaluated; and (iii) certain bacteria were more predominant in fine dust (, , and ) than coarse sediment ( and ), revealing different locations and niches of bacteria in soil, which, depending on wind erosion processes, can have important implications on the soil sustainability and functioning. Infrared spectroscopy showed that wind erosion preferentially removes particular kinds of C from the soil that are lost via fine dust. Our study shows that eroded sediments remove the active labile organic soil particulates containing key microorganisms involved in soil biogeochemical processes, which can have a negative impact on the quality and functioning of the source soil. 相似文献
290.
Fred Van Dyke Autumn Fox Seth M. Harju Matthew R. Dzialak Larry D. Hayden-Wing Jeffrey B. Winstead 《Environmental management》2012,50(5):942-955
Elk (Cervus elaphus) are known to shift habitat use in response to environmental modifications, including those associated with various forms of energy development. The specific behavioral responses underlying these trends, however, have not been effectively studied. To investigate such effects, we examined elk response to habitat alteration near natural gas wells in Las Animas County, Colorado, USA in 2008–2010. We created 10 1-ha openings in forests adjacent to 10 operating natural gas wells by removing standing timber in 2008, with concomitant establishment of 10 1-ha control sites adjacent to the same wells. On each site, we estimated elk use, indexed by pellet density, before and after timber removal. Concurrently, we measured plant production and cover, nutritional quality, species composition and biomass removed by elk and other large herbivores. Species richness and diversity, graminoid and forb cover, and graminoid and forb biomass increased on cut sites following tree removal. Differences were greater in 2010 than in 2009, and elk and deer removed more plant biomass in 2010 than 2009. Elk use of cut sites was 37?% lower than control sites in 2009, but 46?% higher in 2010. The initially lower use of cut sites may be attributable to lack of winter forage on these sites caused by timber removal and associated surface modification. The increased use of cut sites in 2010 suggested that elk possessed the behavioral capacity, over time, to exploit enhanced forage resources in the proximity of habitat modifications and human activity associated with maintenance of operating natural gas wells. 相似文献